Record to something other than mpg, OR post transcode to mp4 on a Mac?


As others have said, it isn’t an MPG vs MP4 issue, it is a file size/network transfer issue. if you made MPG files the same size as the MP4 files, i bet you would not have a problem

Over-the-air HD in the US is about 18 Mbps, per channel after overhead, and with most channels dividing this among 1-2 sub-channels, the actual bandwidth of and individual recording is less. I first started recording MPEG-2 on ATA-100 drives almost a decade ago. You have some type of hardware or networking limitation.

if you are on a 1000 Mbps ethernet network, 18 Mbps will barely be a blip.

if you are on a wireless then you have to worry about latency & all sorts of issues that will affect the streaming higher bandwidth video.

Automatic transcoding is a dire necessity. This was one of my first draws to SageTV back in '08/'09 when ATSC first was rolling out in the US. Video is already transcoded for iOS, etc, so i do not understand the delay in transcode & replace…

personally, i stream, over 802.11/n, ATSC MPEG-2 recordings everyday & have no issues with playback at all.


Unfortunately I no longer have the original file that was giving me issues. However, subsequent recordings of the same series and quality (‘River Monsters’ in HD) have played ok, providing I play them via Channels DVR and not through Plex.

There was definitely something wrong with the original file but, for now, I’m filing it under ‘one of those things’.

My belief that it is an mpg/mp4 issues is simply that mpg by itself plays poorly (in Plex) whereas mp4’s of the same file (transcoded using Handbrake’s Apple TV 1080p preset) play absolutely fine.

I’d be interested to know if Channels is using its own mpg decoder, or whether it’s relying on ATV’s inbuilt abilities (as Plex does).

My network is wireless 802.11ac. The NAS is on a wired segment and connected to the Airport basestation via a gigabit switch. I’ve had no issues streaming full-res Bluray mp4 files via Plex, so I’m reasonably sure that bandwidth isn’t an issue.

To sum up this rather rambling post (sorry!): currently I think this is a non-issue. I’d certainly prefer to use Plex as my interface as I like having all my content under one app, but it’s no biggie. I may still look into that auto-transcode Applescript idea, but purely as an interesting exercise.

Thanks for all the input folks.


Is there any updates on transcode & replace functionality for the DVR?


Not right now. There are numerous other projects ahead of that. You should know that we want it too though! So it’s still on our list.


Has this made it any closer to the top of the list?

A decade ago, before the automated re-encoding flows on SageTV, we could re-encode outside SageTV & via Finder drop it in the recordings directory with the same file name as the original & SageTV would recognize it.

Something like that would even be great with Channels, ie Channels being able to associate files re-encoded with Handbrake, etc but named the same.